Method of reenforcing inner tubes for pneumatic tires



"NW 49 15924. v 1,5139% S'. D. FLOOD METHOD OF REENFORCING INNER TUBESFOR PNEUMATIC TIRES Filed Dec..23 1920 Patented Nov. 4, 1924.

UNITED STATES SAMUEL D. FLOOD, OF KENILWORTH, ILLINOIS.

METHOD OF BEENFORCING INNER TUBES FOR PNEUMATIC TIRES Application filedDecember23. 1920. Serial No. 432,643.

To all whom it may concern:

Be it known that I, SAMUEL D. From), a citizen of the United States,residing at Kenilworth, county of Cook, State of Illinois,

have invented a certain new and useful Improvement in Methods of-Reenforcing Inner Tubes for Pneumatic Tires, and de clare the followingto be a full, clear, and exact description of the same, such as willenable others skilled in the art to which it pertains to make and usethe same, reference being had to the accompanying drawings, which form apart of this specification.

Many attempts have been made to produce inner tubes for pneumatic tireswhich shall have reenforcing tread portions more or lessundercompression so that the tendency thereof will be to close apuncture rather than to make it larger as is the case with theordinaryinner tube in which the rubber is at all points under tension when thetire is inflated; but, so far as I know, there has been no methoddevised for effectively reenforcing an inner tube while the latter is inthe form of a complete undivided ring as distinguished from a meredouble ended tube. Where the reenforcing is applied to a mere tube itnecessitates the forming of a lap joint between the ends of the tubeafter it has been reinforced, for the purpose of fashioning it into acomplete ring, an expedient which is objectionable for many reasons.

The object of the present invention is to 7 produce a simple and novelmethod for effectively reenforcing a completed inner tube in the form ofan annulus, in such a manner that the tread portion thereof will containmaterialwhich, when the tube is inflated,

will be under compression.

The various features of novelty whereb my invention is characterizedwill hereina terbe pointed out with particularity in the claims; but,for a full understanding of my invention and of its objects andadvantages,

reference may be had to the following detailed description taken inconnection with the accompanying drawing, wherein:

Figure 1 is a side elevation of an annular reenforcing element for aninner tubein the form in which it is originally made;

Fig. 2 is a section on an enlarged scale taken approximately on line 2-2of Fig. 1; Fig. 3 is a View similar to Fig. 2, showing the reenforcingelement turned inside-out and ready to be applied to an inner tube;

Fig. 4 is a iew of an ordinary inner tube partly in cross section andpartly in elevation;

Fig. 5 is a view similar to Fig. 4 showing the reenforcing elementassembled upon the inner tube; and

Fig. 6 is a view similar to Fig. 2 showing a slight modification.

In accordance with my invention I form a rubber ring or annulus, 1,U-shaped in cross section, as illustrated in Fig. 2, the same being thenturned inside-out as shown in Fig. 3, so as to bring the trough of the.

ring on the inside. This manipulation of the ring places the materialnear the inner surface thereof under compression. The

ring is then cemented or otherwise secured upon an inner tube, 2, of anyusual or suitable-construction. The parts may be so designed that theinner tube with its reenforcing annulus will fit into the cooperatingcasing in such a manner that there will be no considerable amount ofstretching of the inner tube and therefore no appreciable reduction ofthe compression in the reenforcing element. Because the inner tube andits reenforcing element are both initially made in the form of rings,there will be no tendency to form wrinkles as is the case where astraight tubular element has been rein forced and is then shaped into aring-like structure; and'therefore a frequent cause for damage to theinner tube, which has heretofore resulted from the wearing of the sameat points where wrinkles have occurred, is obviated.

In the event that a nail or other sharp device penetrates the treadportion of the inner tube, it passes through a zone of com pression inthe reenforcing element and the rubber in this element is pressedtightly against the same so as to prevent the discharge of air.Furthermore, upon the withdrawal of the device which has'caused thepuncture, the opening made thereby will instantly be closed.

If desired, the reenforcing annulus may be provided with strengtheningmeans. Thus I have shown in Fig. 3 a reenforcing element, 3, containingwithin the same a layer of fabric, 4.

- I claim:

1. The method of manufacturing a reinforced inner tube for pneumatictires which consists in making a trough in the form of a ring, turningthe ring inside-out, and securing the ring about an inner tube.

2. The method of manufacturing a reinforced inner tube for pneumatictires which 1 consists in making a rubber ring U-shaped in cross sectionturning the ring inside-out so as to bring the trough thereof on theinner side, andthen fitting the ring over an inner tube and securing itthereto.

tion.

SAMUEL D. FLOOD.

In testimony whereof I sign this specifica

